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Journal of Pharmaceutical Analysis 2017年第6期7卷 394-400页

作者： Neeraj kumar Subba Rao Devineni Prasad Reddy Gajjala shailendra kumar dubey Pramod kumar Chemical Research Department Micro Labs LtdAPI DivisionBommasandra-Jigani Link RoadKIADB INDL AreaBommasandraBangalore 560105KarnatakaIndia

One unknown impurity （Imp-II） during the analysis of laboratory batches of isoproterenol hydrochloride was detected in the level ranging from 0.04% to 0.12% by high performance liquid chromatography with UV detection. The unknown impurity structure was proposed as 4-[2-（propan-2oylamino）ethyl]benzene-l,2-diol （Imp-II） using the liquid chromatography-mass spectrophotometry （LC-MS） analysis. Imp-II was isolated by semi-preparative liquid chromatography from the impurity-enriched reaction crude sample. Its proposed structure was confirmed by nuclear magnetic spectroscopy such as 1H, 13C, DEPT （1D NMR）, HSQC （2D NMR） and infrared spectroscopy （IR）, and retention time and purity with HPLC followed by the chemical synthesis. Due to less removable nature of Imp-II during the purification, the synthetic process was optimized proficiently to control the formation of Imp-II below to the limit 〈 0.12% in the course of reaction. The new chemical route was developed for the preparation of this impurity in required quantity with purity to use as reference standard. The most probable mechanism for the formation of Imp-II was discussed in details.

关键词： Isoproterenol hydrochloride Impurities HPLC NMR

Stability and Bifurcation of a Prey-Predator System with Additional Food and Two Discrete Delays

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Computer Modeling in Engineering & Sciences 2021年第2期126卷 505-547页

作者： Ankit kumar Balram dubey Department of Mathematics BITS PilaniPilani CampusPilani333031India

In this paper,the impact of additional food and two discrete delays on the dynamics of a prey-predator model is *** interaction between prey and predator is considered as Holling Type-II functional *** additional food is provided to the predator to reduce its dependency on the *** delay is the gestation delay in predator while the other delay is the delay in supplying the additional food to *** positivity,boundedness and persistence of the solutions of the system are studied to show the system as biologically *** existence of steady states,their local and global asymptotic behavior for the non-delayed system are *** is shown that(i)predator’s dependency factor on additional food induces a periodic solution in the system,and(ii)the two delays considered in the system are capable to change the status of the stability behavior of the *** existence of periodic solutions via Hopf-bifurcation is shown with respect to both the *** analysis shows that both delay parameters play an important role in governing the dynamics of the *** direction and stability of Hopf-bifurcation are also investigated through the normal form theory and the center manifold *** experiments are also conducted to validate the theoretical results.

关键词： predator delay system

Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1561-1572页

作者： Subhasis PRADHAN shailendra kumar Sudhirkumar V.BARAI Department of Civil Engineering Indian Institute of Technology KharagpurWest Bengal 721302India Department of Civil Engineering Guru Ghasidas Vishwavidyalaya(A Central University)Chattisgarh 495009India Department of Civil Engineering Birla Institute of Technologv&SciencePilaniPilani 333031India

The physio-chemical changes in concrete mixes due to different coarse aggregate(natural coarse aggregate and recycled coarse aggregate(RCA))and mix design methods(conventional method and Particle Packing Method(PPM))are studied using thermogravimetric analysis of the bydrated cement paste.A method is proposed to estimate the degree of hydration(a)from chemically bound water(WB).The PPM mix designed concrete mixes exhibit lower *** aggregate concrete(RAC)mixes exhibit higher and a after 7 d of curing,contrary to that after 28 and 90 *** chemically bound water at infinite time(WBo)of RAC mixes are lower than the respective conventional concrete *** lower WBo,Ca(OH)2 bound water,free Ca(OH)2 content and FT-IR analysis substantiate the use of pozzolanic cement in the parent concrete of *** compressive strength of concrete and a cannot be correlated for concrete mixes with different aggregate type and mix design method as the present study confirms that the degree of hydration is not the only parameter which governs the macro-mechanical properties of *** this regard,further study on the influence of interfacial transition zone,voids content and aggregate quality on macro-mechanical properties of concrete is needed.

关键词： recycled aggregate concrete Paricle Packing Method thermogravimetric analysis chemically bound water degree of hydration Fourier transform infrared spectroscopy

Swallowing of Casson fluid in oesophagus under the influence of peristaltic waves of varying amplitude

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International Journal of Biomathematics 2017年第2期10卷 49-64页

作者： Sanjay kumar Pandey shailendra kumar Tiwarit Indian Institute of Technology (BHU) Varanasi 221005 India

The experimentally verified fact that there is a high pressure zone in the lower part of the oesophagus has established that the earlier models fall short of representing the realistic swallowing process in the oesophagus. Since the high pressure is created by gradually increasing amplitudes of peristaltic waves, swallowing of Casson fluid in oesophagus is mathematically remodeled. It is revealed that in the case of exponentially increasing amplitude, pressure is non-uniformly distributed for different cycles. Pressure increases along the entire length of the oesophagus; and finally toward the end of the oesophageal flow, it increases quite significantly, probably to ensure delivery into the stomach. This is a similar observation for Newtonian as well as non-Newtonian fluids but Casson fluids need more pressure; and hence more efforts are required by the oesophagus to transport the fluid forward. When wave amplitude is small, flow rates are small. In such a case, Casson fluid requires higher flow rates for reflux to occur in comparison to Newtonian fluid. This tendency gradually diminishes with increasing amplitude. For a particular value of amplitude, there is no difference; and beyond that the trends are quite opposite. Thus, Casson fluid is found to be less prone to reflux near the wall. It is also concluded that for the Newtonian fluid as well as for the non-Newtonian Casson fluid, reflux is more likely to occur with increasing amplitude and it is further augmented by the addition of amplifying parameter.

关键词： Oesophagus peristalsis varying amplitude Casson fluid.

Multifunctional Bidirectional Charging System for EVs and Grid with Improved Power Quality Using a Sparse Proportionate-NLMF Based Method

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1203-1213页

作者： Dulichand Jaraniya Urvashi Gupta shailendra kumar Arvind Mittal department of Electrical Engineering Maulana Azad National Institute of TechnologyBhopal(M.P.)India Energy Centre Maulana Azad National Institute of TechnologyBhopal(M.P.)India

Electric vehicles(EVs)are one of the more emerging and significant areas,representing the future of ***,the increased demand for EVs brings greater attention toward the development of the charging ***,this paper addresses the multifunctional charging system integrated with the grid,EV battery and household *** presents an improved idea about the charging system with grid connection and its connection to the varying local nonlinear *** consists of a voltage source converter(VSC)tied to the grid and bidirectional converter,which charges/discharges the battery and also regulates the constant voltage across the DC bus,where all the vehicles are connected for *** also shows the operations of charging/discharging the battery of EVs and the voltage and current profile across the battery as per the state of charge(SOC)***,the sparse constrained proportionate normalized least mean fourth(SCP-NLMF)based method is used to control the charging system by estimating the active component of load *** derived mean square error(MSE)of load current is improved due to low convergence rates in later *** adaptation process becomes more accurate by mitigating the MSE error of load current to converge faster and the dynamic response is further *** simulated and tested results validate the accuracy and efficacy of the SCPNLMF technique and charging system.

关键词： Multifunctional charging power quality SCPNLMF voltage source converter

Power Quality Improvement and Signal Conditioning of PV Array and Grid Interfaced Off-board Charger for Electric Vehicles with V2G and G2V Capabilities

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Chinese Journal of Electrical Engineering 2023年第4期9卷 132-143页

作者： shailendra kumar Tapesh Upadhyay Om Hari Gupta Department of Electrical Engineering Indian Institute of TechnologyBhilai 492015India Department of Electrical Engineering Maulana Azad National Institute of Technology(MANIT)Bhopal 462003India Department of Electrical Engineering National Institute of TechnologyJamshedpur 831014India

In this work,we present a photovoltaic(PV)-based off-board charging system integrated with the grid using a voltage source converter(VSC).The control of the grid-tied off-board charger is derived from the joint logarithmic hyperbolic cosine robust sparse adaptive filter(JLHCAF)*** algorithm effectively tracks the fundamental component of the load current in a short duration,providing a good dynamic *** to its robustness against impulsive interference,the JLHCAF outperforms other sparsity-aware robust algorithms The cascaded proportional-integral(PI)controller is used to control the bidirectional buck-boost converter for electric vehicle(EV)charging/discharging,which acts in buck operation if the EV is being charged and in boost operation if it is *** reference DC link voltage for the controller is derived by using adaptive MPPT *** bidirectional properties of the system enable various functions,including grid-to-vehicle(G2V),vehicle-to-grid(V2G),PV source-to-grid(PV2G),vehicle-to-home(V2H),and PV source-to-vehicle(PV2V)***,the system can supply power to critical nonlinear *** control strategy ensures compliance with the power quality requirements set by the IEEE standard,as demonstrated in the *** validate the effectiveness of the proposed system,we conducted tests under dynamic conditions by disconnecting and reconnecting household ***,the off-board charging system was subjected to actual conditions,such as variations in solar PV insolation,and its steady-state performance was evaluated through simulation and laboratory experimental *** results,including total harmonic distortion(THD),support the validation of the developed charging system.

关键词： Grid to vehicle(G2V) vehicle to grid(V2G) off-board charger(OBC) power quality total harmonic distortion(THD) electrical vehicles(EVs)

Sulfamic acid as a green,reusable catalyst for stepwise,tandem&one-pot solvent-free synthesis of pyrazole derivatives

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Chinese Chemical Letters 2017年第7期28卷 1571-1576页

作者： Veera Swamy Konkala Pramod kumar dubey Department of Chemistry Jawaharlal Nehru Technological University HyderabadCollege of EngineeringKukatpally 500085India

Sulfamic acid（SA） is a bi-functional, cost-effective and reusable green catalyst for the synthesis of 4-（pyrazol-4-yl）methylenepyrazol-5（4H）-one derivatives by one-pot, three-component condensation of pyrazol-4-carbaxaldehydes, b-ketoesters and phenyl hydrazine（Route-I）. In addition to this method,another simple condensation of pyrazol-4-carbaxaldehydes with pyrazolone in the presence of SA under the solvent-free condition in good yield is reported. The merits of these protocols are mild conditions,non-aqueous workup, high yields, easy availability of the catalyst, no chromatographic separation and inexpensive solid acid catalyst. Furthermore, SA could be recycled and reused for five times without losing its catalytic activity.

关键词： Pyrazol-4-carbaxaldehydes Knoevenagel condensation Sulfamic acid Multicomponent reaction Physical grinding

A threshold voltage model of short-channel fully-depleted recessed-source/drain(Re-S/D) SOI MOSFETs with high-k dielectric

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Chinese Physics B 2015年第10期24卷 604-611页

作者： Gopi Krishna Saramekala Sarvesh dubey Pramod kumar Tiwari Department of Electronics and Communication Engineering National Institute of Technology Shri Ramswaroop Memorial University

In this paper, a surface potential based threshold voltage model of fully-depleted（FD） recessed-source/drain（Re-S/D）silicon-on-insulator（SOI） metal-oxide semiconductor field-effect transistor（MOSFET） is presented while considering the effects of high-k gate-dielectric material induced fringing-field. The two-dimensional（2D） Poisson＇s equation is solved in a channel region in order to obtain the surface potential under the assumption of the parabolic potential profile in the transverse direction of the channel with appropriate boundary conditions. The accuracy of the model is verified by comparing the model＇s results with the 2D simulation results from ATLAS over a wide range of channel lengths and other parameters,including the dielectric constant of gate-dielectric material.

关键词： recessed-source/drain (Re-S/D) high-k gate-material fringing field and SCEs

Vacuum press drying studies on two fast-growing Indian wood species

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Journal of Forestry Research 2018年第3期29卷 857-862页

作者： shailendra kumar Rushikesh R.Topare Jitendra Nagar Forest Products Division Forest Research InstituteDehradun Uttarakhand 248006 India

Two fast-growing Indian species, Melia composita Benth. and Eucalyptus tereticornis Sm., which have different sets of physical properties, were dried together in a vacuum press dryer(VPD) under two drying conditions,i.e., above boiling point(ABP) and below boiling point(BBP). The ABP and BBP conditions were maintained by keeping the temperature constant at 75 ℃ and maintaining two pressure levels: 300 mm of Hg(ABP) and 450 mm of Hg(BBP). In order to understand pressure conditions at the core during vacuum drying, a cylindrical brass pipe was inserted in both wood cores and attached with pressure gauges placed outside of the VPD. The results indicate that the Melia wood core attained equilibrium pressure immediately with the pressure of VPD, while Eucalyptus attained it very slowly, reaching equilibrium at later stages of drying when cracks and checks advanced to the *** drying rate was higher for Melia than Eucalyptus under both drying conditions. The drying rate of Melia(ABP) was higher than Melia(BBP), however, the drying rate for Eucalyptus(ABP) was not significantly different from the BBP drying rate.

关键词： Vacuum press drying Melia composita Eucalyptus tereticornis Boiling point Wood core pressure

Multilayer Self-Defense System to Protect Enterprise Cloud

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Computers, Materials & Continua 2021年第1期66卷 71-85页

作者： shailendra Mishra Sunil kumar Sharma Majed A.Alowaidi College of Computer and Information Sciences Majmaah UniversityMajmaah11952Saudi Arabia

A data breach can seriously impact organizational intellectual property,resources,time,and product *** risk of system intrusion is augmented by the intrinsic openness of commonly utilized technologies like TCP/IP *** TCP relies on IP addresses,an attacker may easily trace the IP address of the *** that many organizations run the risk of data breach and cyber-attacks at a certain point,a repeatable and well-developed incident response framework is critical to shield *** cloud possesses the challenges of security,lack of transparency,trust and loss of *** eases quickens the processing of information but holds numerous risks including hacking and confidentiality *** risk increases when the organization outsources the cloud storage services through the vendor and suffers from security breaches and need to create security systems to prevent data networks from being *** business model also leads to insecurity issues which derail its *** attack mitigation system is the best solution to protect online services from emerging *** research focuses on cloud computing security,cyber threats,machine learning-based attack detection,and mitigation *** proposed SDN-based multilayer machine learning-based self-defense system effectively detects and mitigates the cyber-attack and protects cloud-based enterprise *** results show the accuracy of the proposed machine learning techniques and the effectiveness of attack detection and the mitigation system.

关键词： Cybersecurity cyber threats cyber-attacks attack mitigation system